1. Technical Field
The present invention relates to an image forming apparatus which forms an image on a medium by discharging liquid from a discharge head.
2. Related Art
In the past, as this type of image forming apparatus, an image forming apparatus has been proposed in which the ink in the discharge head or a tank which is mounted on a carriage is agitated by reciprocating the carriage in a main scanning direction (refer to JP-A-2004-1411, for example). Since pigment ink is ink in which pigment particles are dispersed in a solvent, if it is neglected over a long period of time, the pigment particles settle, so that the concentration of pigment becomes non-uniform in an upper portion and a lower portion of the tank. For this reason, a configuration is made such that the concentration of ink can be uniformized by reciprocating (blank scan) the carriage in the main scanning direction without discharge of ink from a recording head.
Usually, the carriage has a carriage belt attached thereto and is also slidably mounted on a carriage guide disposed along in the main scanning direction, and the carriage is reciprocated while being guided by the carriage guide by driving the carriage belt by a carriage motor. At this time, in order to perform agitation of ink in a short time as much as possible, it is desirable to make the speed of reciprocation of the carriage faster than that at a normal time (the time of image formation) or narrow the width of the reciprocation. However, in some cases, there is concern that a load may be concentrated on the specific portion of the carriage belt or the carriage guide. On the other hand, it is also considered to increase the rigidity of the carriage belt or the carriage guide. However, weight increases or an increase in size is caused.